ISO 8139:2018

Overview

ISO 8139:2018 is an international standard that specifies the mounting dimensions of rod-end spherical eyes used in pneumatic fluid power cylinders operating at 1,000 kPa (10 bar). These rod-end spherical eyes enable mechanical force transmission from piston rods under oscillatory rotational and tilting movements, ensuring compatibility and interchangeability in pneumatic cylinders manufactured according to related ISO standards such as ISO 6432 and ISO 15552.

Designed to meet the demands of pneumatic systems operating at 10 bar pressure, ISO 8139:2018 provides precise dimensional requirements and application instructions to enhance system reliability, durability, and ease of installation in pneumatic cylinder assemblies.

Key Topics

• Mounting Dimensions: Detailed specifications for rod-end spherical eyes are provided, including dimensions for mating components, tilt angles (±4°), and tolerances necessary for seamless interchangeability.
• Compatibility: The standard supports rod-end spherical eyes designed specifically for 1,000 kPa series cylinders per ISO 6432 (small bore cylinders) and ISO 15552 (larger bore cylinders) but does not limit usage in other applications.
• Installation Guidelines: Recommendations such as using m6 tolerance shafts for fitting, alternative f7 tolerance with case-hardened shafts, and locking nuts to secure the spherical eyes during operation.
• Bearing Life Factors: Insight into factors affecting bearing life is discussed, including load type, lubrication frequency and type, direction and angle of load oscillation.
• Lubrication Requirements: Emphasizes the necessity of sufficient lubrication under varying operating conditions to maintain performance and durability.
• Ordering Designation: Clear format for specifying rod-end spherical eyes including bore diameter and material surface type for procurement and manufacturing.

Applications

ISO 8139:2018 is critical in industries and applications where pneumatic fluid power systems are employed to convert compressed air energy into mechanical motion. Typical applications include:

• Automation and Robotics: Ensures reliable and standardized cylinder connections in automated manufacturing lines.
• Material Handling Equipment: Facilitates consistent performance in pneumatic actuators controlling conveyors and lifts.
• Machine Tools: Supports precise linear actuation with oscillating or tilting rod-end connections.
• Automotive Manufacturing: Provides standardized rod-end parts to maintain quality and interchangeability in pneumatic tooling systems.
• Packaging Machinery: Enhances durability and quick maintenance of pneumatic cylinders through compatible mounting dimensions.

The standard is valuable to designers, manufacturers, maintenance professionals, and quality controllers working with pneumatic cylinders operating at 10 bar pressure, aiming for durability and global interchangeability.

Related Standards

Practitioners using ISO 8139:2018 will benefit from familiarity with the following related ISO standards, which complement and expand the pneumatic cylinder specifications:

• ISO 6432: Single rod cylinders, 1,000 kPa series - defines basic and mounting dimensions for small bore pneumatic cylinders (8 mm to 25 mm).
• ISO 15552: Cylinders with detachable mountings, 1,000 kPa series - covers larger bore cylinders (32 mm to 320 mm) including basic and accessory dimensions.
• ISO 21287: Compact cylinders, 1,000 kPa series - specifications for compact pneumatic cylinders with bores from 20 mm to 100 mm.
• ISO 6099: Identification code for mounting dimensions and types of cylinders.
• ISO 5598: Vocabulary for fluid power systems and components, ensuring clear, standardized terminology.
• ISO 286-2: Tolerance classes for linear sizes, relevant for shaft and bearing fitment.

These standards collectively ensure consistency and interoperability in pneumatic fluid power systems worldwide, enhancing product quality and system efficiency.

By adhering to ISO 8139:2018, manufacturers and users of pneumatic cylinders achieve mechanically reliable, interchangeable rod-end spherical eyes tailored for 10 bar pneumatic systems, supporting global industrial applications requiring standardized fluid power components.